Ending on an equinox
One hundred and eighty degrees along the ecliptic from the March equinox, the Sun crosses back over the celestial equator, this time heading south. Day and night are close to equal, and that instant is the start of Libra. Virgo therefore closes on an event that half the world notices, even if the opening of the sign a month earlier passes without comment.
The equinox does not fall at a fixed clock time. The interval between successive September equinoxes averages about 365.2422 days, and the calendar handles the leftover quarter day with a leap year, so the moment slides later through three ordinary years and then jumps back. Its calendar date currently wanders between the 22nd and the 23rd of September and has occasionally touched the 21st.
How long the sign takes
Virgo runs to about 30.9 days. Earth passed aphelion in early July and is picking up speed as it falls back towards the Sun, so each sign from Leo onwards is fractionally shorter than the one before. Virgo sits on that descending part of the curve, faster than Leo and slower than Libra.
The variation across the whole year is worth stating plainly, because most published date ranges hide it. Every sign covers the same thirty degrees of sky, but the time the Sun takes to cross them ranges from about 29.5 days near January's perihelion to about 31.5 days near July's aphelion. That is a two day spread, and a range rounded to whole calendar days simply cannot express it. The days column in the table gives the figure for the year you have picked.
Mercury, earth and the reading of the month
Virgo is a mutable earth sign and the second of Mercury's two signs, the other being Gemini. Mutable signs close a season, so Virgo is the part of the year in which summer is visibly finishing. Earth signs are read as practical and evidence-led, and Mercury in an earth sign is taken as analysis applied to material things rather than to conversation, which is where the sign's association with detail, correction and craft comes from.
Because Mercury rules both Virgo and Gemini, any Virgo placement is interpreted alongside Mercury's own position in the chart, in the same way that Aries placements are read with Mars. The two signs are not interchangeable despite the shared ruler: Gemini is air and gathers, Virgo is earth and sorts.
Borderline birthdays and hemispheres
Birthdays around 22 and 23 August, or 22 and 23 September, are the ones where a printed range is least trustworthy. There is no Leo-Virgo cusp and no Virgo-Libra cusp. At any given instant the Sun occupies a single ecliptic longitude, and that longitude sits inside one sign and not between two. A cusp describes the gap in a date range, not a condition of the sky.
Settling it requires the birth date, the birth time and the time zone that was actually in force at that place on that day. Historical zone changes and wartime or seasonal clock rules are the usual source of error, and applying the modern rule to a mid twentieth century birth can shift the calculation by an hour.
The ingress itself is a single worldwide moment, so the dates are identical in every country. In the southern hemisphere Virgo closes the winter quarter and its equinox is the spring one, which reverses the harvest imagery that European astrology attached to the sign.
Questions people ask about this
When does Virgo season end?
At the September equinox, which currently falls on the 22nd or 23rd. That instant is also the start of Libra. The table above gives the exact time in UTC for whichever year you have selected.
Are the Virgo dates 23 August to 22 September?
That is the common approximation. In recent decades the entry has often fallen on 22 August instead, and both boundaries move by up to a day across the leap year cycle, so the range is a summary rather than a reliable answer for an edge birthday.
Why do Virgo and Gemini share a ruler?
Traditional rulership gives each planet other than the Sun and Moon two signs, one on each side of the zodiac. Mercury takes Gemini and Virgo. The signs still read very differently because one is mutable air and the other mutable earth.
Is Virgo season autumn?
It is the last month of summer in the northern hemisphere and ends exactly as autumn begins. In the southern hemisphere the same dates close winter and end at the spring equinox, while the times themselves are unchanged.
How much does the Virgo start date really move?
Across a normal leap year cycle it varies over roughly a day, sitting on 22 or 23 August depending on the year and the time zone you convert into. That is enough to change the sun sign of anyone born within a few hours of the crossing.